Tripods with adjustable legs are typically used for supporting equipment such as cameras, surveying instruments and the like. Typically, the tripod will have three adjustable supports, each support having a pair of legs which diverge upwardly from the foot to the mounting plate for the equipment. Each leg has a fixed leg member attached to the plate and a sliding leg member telescopingly attached to the fixed leg member.
The typical mechanisms for locking the adjusting legs at a desired length have presented an assortment of disadvantages. For example, many of the previous mechanisms used knobs, screws or twisting devices which can strip, jam, or in cold weather, freeze the lock during use. Even when properly operating, these mechanisms are generally slow and cumbersome to lock, requiring two separate actions and multiple rotations of the knob to properly lock. Such characteristics are particularly disadvantageous when a quick set-up is required for heavy loads such as portable news cameras in the field. The previous mechanisms have also required considerable manual force to be properly locked. In addition, it was difficult to determine when the locking mechanism is properly locked. If the knob mechanism is rotated too much, the screw may damage the leg members whereas, if the knob mechanism is rotated an insufficient amount, the screw may not lock the leg and the expensive and heavy equipment might fall and be damaged.